The Taliban attack on an army base outside Mazar-e Sharif on Friday was the deadliest single attack on a military installation in the entire 16-year history of the Afghan conflict.  The Taliban subterfuge had been particularly thorough.

The Taliban fighters arrived in Ford Ranger trucks painted in a perfect facsimile of Afghan army vehicles.  They had full uniforms and plausible paperwork; one of the team was disguised as a casualty complete with a bloodied bandage around his head and an IV drip in his arm.  The 10 Taliban attackers are believed to have killed around 170 Afghan soldiers. 

Officially the spring offensive has not started yet this year.  Nevertheless last month the Taliban retook the key district of Sangin in the southern Afghan province of Helmand; a significant strategic advance.  Public statements about the US mission have increasingly focused on the effort to tackle IS and other international terrorist organisations in Afghanistan.  But the truth is the US recognises that the main threat to the Afghan government comes from the Taliban, and so the overwhelming focus of American involvement here remains anti-Taliban.

Taliban successes in the almost two and a half years since the Nato combat mission in Afghanistan officially ended have led senior Afghan officials and American top brass here to argue that the US needs to boost its training and assistance mission.  The suggestion is a few thousand more troops are needed.  It emphasises once again the key problems the Afghan forces face: inadequate training and a lack of commitment from recruits, exacerbated by terrible conditions, corruption in the officer class and poor air support.

Read more: BBC News